I've set up and run my own physical Linux server as well as cloud ones and it may be easier to get a Linux box up and running with an application but to get it into a state I consider production ready it's much harder. With ECS (or similar offerings, I agree kubernetes can be overkill) you get logging, blue green deployments, permissions, secret management, scaling, and more built in. You don't need to worry about upgrading your server and there's a whole category of security issues you don't really need to worry about. I work in a space with some compliance requirements and I do not think we could meet them at the size that we are without offerings like this.